The dreaded FTP

[Marcv]

I think two things to add:

 

1) have you calibrated your trainer? you said it was new, they always need to be calibrated. you can run your stages power meter on your IDT to check if they are similar.

2) because of drive train efficiency losses i find the IDT always has a lower ftp than a pedal power meter. 

 

the other simple check is, when on zwift how does 265w feel? check it against your heart rate. At ftp your heart rate should be pretty high. Another test is to hold 120% of FTP, if you can do this for longer than 5 minutes easily then you should probably retest.

[RocknRolla]

Did you do an outside FTP?

there are some specific parameters you need to try and achieve in terms of road, gradient etc to get “accurate “ ftp.

 

also, leading up to an FTP, one should ideally be rested, or well tapered. So doing one indoors today, and another tomorrow, will not be advisable.

[MTB-More]

I think two things to add:

 

1) have you calibrated your trainer? you said it was new, they always need to be calibrated. you can run your stages power meter on your IDT to check if they are similar.

2) because of drive train efficiency losses i find the IDT always has a lower ftp than a pedal power meter. 

 

the other simple check is, when on zwift how does 265w feel? check it against your heart rate. At ftp your heart rate should be pretty high. Another test is to hold 120% of FTP, if you can do this for longer than 5 minutes easily then you should probably retest.

 

I did calibrate a few time. 265w feels like 320w outside so it feels a lot harder. ERG also doesnt help here cause when it starts to bite it just gets worse. 

Problem is the Stages is on my Rocky with GXP and the bike I have on the IDT is a cheapy so cant run both to link them and test. I might be upgrading the M2 to a Elite Suito soon so will be able to run and link them together

 

 

Did you do an outside FTP?

there are some specific parameters you need to try and achieve in terms of road, gradient etc to get “accurate “ ftp.

 

also, leading up to an FTP, one should ideally be rested, or well tapered. So doing one indoors today, and another tomorrow, will not be advisable.

 

No was done inside on a Ramp test. The Stages one is from outside prolonged rides 2h+ that gives a estimate of 235 FTP. Also I have been training for 12 days straight so might need to take a day off to do the FTP... 

Edited May 1, 2020 by MTB-More

[RocknRolla]

You would need to take more than a day. 

[Jakkals.]

I'm just thinking here....theres a few ways to solve this. 

1. calibrate your smart trainer. perform a spin down etc.

2. auto power match if that is available. so you basically let your smart trainer read what your stages is giving.

3. manual power adjust, ride in free mode. get to ftp with your stages by getting the figure from your garmin, now look at zwift is telling you what your smart trainer is doing...if it under reads, adjust according to the %.

 

Good luck.

[mecheng89]

I'm no professional but in my humble opinion these apps and bike computers like Garmin that estimate your FTP are not accurate - Yes they will do if thats the only system of measurement you have. A proper PM like you have (Stages) is the one i'd go with as its measuring your power at the pedals in real time and probably the most accurate.

 

I also think that a FTP test outside on the bike will be different than an FTP test on an indoor trainer. for IDT work you should train on the same trainer that you did your FTP test on - You cannot or should not test on one device (Like in a gym) and then use that FTP at home on your IDT - Rather have an FTP for the gym bike and one for your IDT.

+1

My indoor FTP exceeds my outdoor one. So you must decide which number you want to base things like TSS, IF on, for recovery purposes. A high TSS ride outdoors should exceed that of the equivalent distance ride indoors. If you use more than 1 PM, you should have more than 1 data analysis software that is dedicated to the data from the respective PMs.

 

I use Xert with my own Magnus M2, so the indoor training data goes on there, whereas outdoor rides go onto my Garmin Connect account. 

[Help.Me.]

@ OP , have you compaired your results with intervals.icu? Just out of curiosity , maybe you will get a "better" result...